Alzheimer’s and Macular Degeneration

November 26, 2016

One change that occurs in the retina of people with AMD as the disease progresses is an increase in the number and size of fatty deposits called drusen.

In their study paper, the researchers explain that the causes of AMD are understood to be complex, with both genetic as well as environmental risks factors, and share similarities with Alzheimer’s disease.

They note how recent studies have shed a lot of light on the genetic causes of AMD – although this is not matched by insights into the molecular mechanisms involved.

However, they also note that other studies have found aged and AMD retinas also show accumulation of the types of beta-amyloid proteins that are found in toxic plaques in the brains of people with Alzheimer’s disease, and “for which there appears to be no clear genetic basis.”

For their study, Dr. Arjuna Ratnayaka, a lecturer in vision sciences at Southampton, and colleagues used cell cultures and mouse models of AMD to investigatemechanisms of Alzheimer’s beta-amyloid accumulation inside retinal cells.

They were particularly interested in the speed with which the proteins find their way inside the retinal cells.

The researchers found the retinal cells internalized the amyloid proteins within 24 hours of being exposed to them.

They also discovered that the amyloid proteins are retained inside the retinal cells, where they gradually impair a molecular mechanism reliant on the protein encoded by the MAP-2 gene. Among other things, MAP-2 mechanisms help to maintain important structures inside cells called microtubules.

Dr. Ratnayaka says they were surprised at the speed with which the amyloid proteins entered the cells, and he suggests the finding may help explain how a healthy retina can switch to a diseased, AMD retina.

The team is now planning to evaluate how the beta-amyloid proteins actually enter the retinal cells and set about causing internal damage. The hope is the continuing work will lead to measures to prevent or treat AMD.

For more info:

http://www.medicalnewstoday.com/articles/314302.php

http://www.belmarrahealth.com/age-related-macular-degeneration-linked-alzheimers-disease/

http://www.express.co.uk/life-style/health/734691/protein-macular-degeneration-AMD-alzheimer-s-disease-blindness-eye-retina-amyloid-beta

 

 

 

 

 

 


More Info on the Book Eye 4

November 17, 2016
Here are a few more notes on the Book Eye 4 as a resource for low-vision/blind users.  Johnathon Kirk of UNC has sent us a brief description of his experience with the Book eye.
He highly recommends it as a free book scanner and reader.  see below
Lauren Tappan
bookeye-4

More Info on the Book Eye4 Scanner

November 8, 2016

The following is from Lauren Tappan.

Many University libraries’ now have the Book Eye 4.  Jack Mitchell from Indigo Logics,
Johnathon Kirk from the Duke Eye Center, my husband and I met at the Duke Library with
the goal of using the Book Eye 4, my I-Pad and the KNFB Reader to have scanned files
read to me.
The Book Eye 4 is a great document scanner that will allow you to send scanned documents to a thumb drive or PDF file.  It has large print on the navigational desk top so it would be easy for a low-vision user.
   My goal was to scan a document on the Book Eye 4 and send this
scanned document to my I-Pad e-mail program.
   Unfortunately, my I-Pad Voice Over does not read PDF files so we were trying to
figure out a way to have these scanned documents read.
  Jack Mitchell showed us how we can send the PDF file to my KNFB Reader ap
where the document can be saved and read to me in a timely fashion.
   As a low-vision user of these devices, I was looking for a quick and easy
scanning system that would allow me to scan at least 20 pages at a time.
When I have tried to use the KNFB Reader to scan material sometimes
my hands are not steady enough and I don’t get a clear copy of the page.
  Jack Mitchell showed us a way to arrange the I-Pad on a flat surface,
exposing the camera and then being able to use the I_pad and KNFB
Reader like the Book Eye 4 scanner.
  It sounds complicated but once you know the system things go quickly.
Lauren

Cats and Low Vision

October 29, 2016

The following is from the Albuquerque Journal:

Q: I have friends that have macular degeneration. One is legally blind. I have read internet articles telling that cats can carry the parasite Toxoplasma gondii.

One of them states that toxoplasmosis is the most common cause of eye inflammation in the world. Could this be causing the eye problems that our long-term cat owner friends have?

Dr. Nichol: Toxoplasmosis is a zoonotic disease, meaning that it is transmissible between animals and humans. It’s caused by a single-celled protozoan parasite that can infect any warm-blooded mammal but cats are its definitive host.

I sent your question to human ophthalmologist Dr. Jesse Swift.

The good doctor’s comments: “Toxoplasmosis is a common parasite that usually does not affect healthy individuals. It can, however, affect those that are immunosuppressed due to cancer treatment, HIV/AIDS, or other reasons. It can also affect the fetus in a pregnant woman. The children that contract congenital toxoplasmosis can develop hearing loss, mental disability, and blindness. In fact, toxoplasmosis is a leading cause of blindness especially in underdeveloped countries. It is also a leading cause of uveitis or eye inflammation in both children and adults. In those that are immunosuppressed it can cause life threatening encephalitis.”

Another human ophthalmologist, Dr. Stephen Saxe, was also kind enough to weigh in. “Toxoplasmosis and age-related macular degeneration are both diseases that can affect the retina and the macula (the anatomical visual center of the retina). They both can cause inflammation and scarring in the retina. However, toxoplasmosis and age-related macular degeneration are two separate diseases caused by two completely different mechanisms.”


Book Scanning Facility

October 22, 2016

The following is from Lauren Tappan

bookeye-4

“Duke University East Campus Library now has the Book Eye 4.
You do not have to be a Duke student to use this
AT equipment.
  You put a book on their scanner and you can scan
this written material to a USB thumb drive or send it
to an e-mail address.
  Quick and easy to use.”
Lauren

Book > 100 Questions & Answers About Macular Degeneration

October 4, 2016

100 Questions & Answers About Macular Degeneration

Whether you’re a newly diagnosed patient, or a friend or relative of someone suffering with macular degeneration, this book offers guidance and support

This book provides authoritative, practical answers to commonly asked questions about this condition to help you better understand all aspects of dealing with macular degeneration including treatment options, sources of support, and much more. It’s an invaluable resource for anyone coping with the disease’s physical and emotional turmoil.

For more info:

http://ovid.com/site/catalog/books/8437.jsp


Potential Treatment for RP and AMD

October 4, 2016

New research published in Cell Reports identifies a potential treatment target for blinding diseases such as retinitis pigmentosa and advanced dry age-related macular degeneration. In the study, researchers at Washington University in St. Louis School of Medicine explored how the retina’s photoreceptors — the rods and cones responsible for detecting light, color, contrast, and sharpness — are damaged over the course of these diseases.

Lin, Apte and colleagues at Washington Univ. found that defects in the same NAD pathway appear to be involved in several different diseases of the retina. When they treated damaged photoreceptor cells in mice with a second molecule called NMN — a precursor molecule that boosts levels of NAD — the cells’ degeneration ceased and vision was restored.

“This is exciting because we may have found a reason why these highly metabolically active cells are susceptible to damage and death when the NAD pathway does not function optimally,” said Apte, also a professor of developmental biology and neuroscience and of medicine.

The pathway offers a promising target for therapies for multiple retinal diseases, including retinitis pigmentosa, a cause of blindness that impairs vision over many years and for which there is currently no cure.

for more info:

https://www.sciencedaily.com/releases/2016/09/160928141908.htm